Remote Detection of Trichloroethylene in Soil by a Fiber-Optic Infrared Reflectance Probe

A remote detection method for measuring the infrared reflectance from chlorinated hydrocarbons in soils is demonstrated. The method uses a 12-m-long, field-ruggedized, chalcogenide fiber to transmit IR reflectance data to a remotely located FT-IR spectrometer. Minimum observable signal corresponding to 250 ppm of trichloroethylene (TCE) in sand was measured with the system. Suggestions for improving the threshold detection limit are offered.